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          <span class="refentrytitle">biquada</span>
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        <p>biquada — 
      A sweepable general purpose biquadratic digital filter with a-rate parameters.
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        <h2>Description</h2>
        <p>
      A sweepable general purpose biquadratic digital filter.
    </p>
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        <h2>Syntax</h2>
        <pre class="synopsis">ares <span class="command"><strong>biquada</strong></span> asig, ab0, ab1, ab2, aa0, aa1, aa2 [, iskip]</pre>
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        <h2>Initialization</h2>
        <p>
      <span class="emphasis"><em>iskip</em></span> (optional, default=0) -- if non-zero, intialization will be skipped. Default value 0. (New in Csound version 3.50)
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        <h2>Performance</h2>
        <p>
      <span class="emphasis"><em>asig</em></span> -- input signal
    </p>
        <p>
      <span class="emphasis"><em>biquada</em></span> is a general purpose biquadratic digital filter of the form:
      </p>
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          <p><br />
  a0*y(n) + a1*y[n-1] + a2*y[n-2] = b0*x[n] + b1*x[n-1] + b2*x[n-2]<br />
      </p>
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        <p>
      This filter has the following frequency response:
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         B(Z)   b0 + b1*Z<sup>-1</sup>  + b2*Z<sup>-2</sup><br />
  H(Z) = ---- = ------------------<br />
         A(Z)   a0 + a1*Z<sup>-1</sup>  + a2*Z<sup>-2</sup><br />
      </p>
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        <p>
      This type of filter is often encountered in digital signal processing literature. It allows six user-defined a-rate coefficients.
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        <h2>See Also</h2>
        <p>
      <a class="link" href="biquad.html" title="biquad"><em class="citetitle">biquad</em></a>
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        <h2>Credits</h2>
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            <td>Author: Hans Mikelson</td>
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            <td>October 1998</td>
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        <p>New in Csound version 3.49</p>
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